Codes P0430, P0171, P0174 and P0300?

1977WIMMS

MEMBER
2005 FORD TAURUS
3.0L
V6
2WD
AUTOMATIC
111,500 MILES

I scanned the car for codes due to my check engine light coming on and it gave me these codes p0430 twice, p0171, p0174 and p0300. I looked up possible causes and I'm getting vacuum line leak, maybe the gasket for throttle body or air intake, plugs and wires which are both brand new, catalytic convertor, 02 sensor and now I just need to know how and where to start on finding the leak if this is the case if not then what are your thoughts and recommendations on the codes it's got a new alternator, battery, plugs wires, oil change, and air filter. However, if I'm driving I can hear what I think sounds like a roar or growl like humming sound only when accelerating that gets quieter when I slow down or take my foot off the gas, but if I'm in the passenger seat I don't seem to hear it and when I start it more times than not it idles rough but starts. Please any advice is greatly appreciated. Thank you

2 Replies

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

Is the noise you hear loud enough for you to record and upload for me to hear? If so, could you possibly do that?

As far as the codes are concerned, two of them are lean codes which indicate either a vacuum leak as you mentioned, or it could be a low fuel pressure issue.

Now, if there is an exhaust leak before the catalytic converter, which can cause a lean code, I need to confirm what you are hearing isn't a leak.

To get you started, take a look through this link. It explains how to locate and repair an engine vacuum leak.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If you are unable to find a leak, we will need to check the fuel pressure. Here is a link that explains in general how that is done.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

I attached a pic below providing the manufacturer's fuel pressure specifications.

Let me know.

Take care,

Joe

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